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Chinese develop pesticide to reduce contamination

Chinese researchers have developed a new pesticide with nano slow-releasing technology that can increase efficiency and decrease pollution in the soil.

A team led by Wu Zhengyan of the Hefei Institute of Physical Science under the Chinese Academy of Sciences said this on Thursday.

Zhengyan said soluble starch was used as a template and porous calcium carbonate micro spheres as carriers to make a nano-controlled release pesticide.

It can control the migration of pesticide molecules in the environment, reducing pesticide loss and damage to environment.

The results were recently released in an academic journal published by the American Chemistry Society called the ACS Sustainable Chemistry and Engineering.

Zhengyan said China’s agriculture industry relies heavily on the use of pesticides, using an estimated more than one million tonnes annually.

However, only 30 per cent of pesticides have an effect on crops and the rest are simply washed away.

Conventional farming, therefore, requires several rounds of pesticide spraying each day, which not only raises the cost, but also causes serious environmental contamination and excessive pesticide residue.

Zhengyan says the pesticide release technology is environmentally friendly and cost efficient, providing a good solution to bottlenecks in China’s agriculture industry.

Bacterial communities that live on amphibian skin could provide vital clues to individual species’ vulnerability to the chytrid fungus Batrachochytrium dendrobatidis (Bd), which is currently decimating amphibian populations worldwide, according to a pioneering new genetic study led by international conservation charity ZSL (Zoological Society of London) and published in the journal Nature Communications.

The research, conducted in partnership with the Spanish National Research Council (CSIC) and Imperial College London, used more than a decade of data collected from midwife toads (Alytes obstetricans) in the French and Spanish Pyrenees to investigate why certain populations of this species demonstrated a degree of resistance to Bd, while elsewhere the disease has contributed to catastrophic declines in similar animals.

Previous studies indicate that the outcome of infection is linked to the virulence of the particular Bd strain, but more recent evidence suggests that bacteria living naturally on amphibian skin can actually provide protection from the fungus.

Lead author Kieran Bates from Imperial College London and ZSL’s Institute of Zoology comments: “We were surprised to find that populations of midwife toads suffering severe Bd-driven declines all possessed very similar skin microbial communities, which were themselves distinct from those in populations proving more resistant to the chytrid pathogen."

“What these findings mean in practice is that skin microbes may play a more central role in dictating disease outcome for amphibians than was previously thought. Our next goal is to determine exactly how these skin microbes may be protecting the toads. This would open up exciting new possibilities with conservation applications that may protect this and other species from disease.”

Senior co-author Dr Xavier Harrison from ZSL’s Institute of Zoology adds: “What’s really interesting about our findings is that there appears to be no obvious geographic relationship between individual toad populations and resistance to disease. Nor did we find evidence that declines in response to the presence of Bd were associated with unique genetic variants of the pathogen. This leaves us with the exciting possibility that skin microbes in Bd-resistant populations may actually be protecting the toads in question from the disease.”

Following this discovery, the team’s next priority is to determine exactly how skin microbes may be protecting the toads from chytrid. By shedding light on this amphibian-microbe relationship, it is hoped that they will open up exciting new approaches to the future conservation of this and other species.

New Super-Heavy Element 117 Confirmed

The periodic table has been extended, with the announcement of the confirmation of the yet to be named element 117.
In 2010 a US Russian collaboration announced they had produced atoms of an element with 117 protons, filling a gap that appeared when 118 was made four years earlier. However International Union of Pure and Applied Chemistry (IUPAC) insists on corroboration by two independent teams before it allows new elements to be added to the Periodic Table, although a temporary name of Ununseptium is in use until confirmation has been made. It has taken four years, but this appears to have finally arrived.
Hinde was part of a team at the GSI laboratory in Germany who fused calcium 48 and berkelium 249. This is not easy, because berkelium 249 is both hard to produce in substantial quantities and has a half life of 320 days. Less than half of any amount produced will still be around a year after it was made, which means transportation and purification can't wait. The resulting product, like all atoms heavier than lead, was unstable. By watching the alpha particles emitted the team concluded that these were the product of two decay chains, both originating with 294117, that is an atom with 117 protons and 177 neutrons. One of the chains included the isotopes 270Db and266Lr, the latter adding four neutrons to the previous highest isotope of lawrencium.
In general large atoms have shorter half lives, that is decay more quickly through radiation, as their masses become greater. However, what are know as islands of stability exist, and the authors believe the one hour half life of 270Db "marks an important step towards the observation of even more long-lived nuclei of superheavy elements located on an "island of stability.'"
The manufacturing process was hardly efficient. More than 1019 atoms of 48Ca, not a common isotope in its own right, were fired at the berkelium to produce just four atoms of 117. Nevertheless, Hinde says, "On the basis of this paper it is likely that element 117 will be accepted."
Element 117 is the most recent of six elements first announced by the Joint Institute for Nuclear Research in Russia. Of these 113, 115 and 118 remain unconfirmed, although claims have been made for the first two.
Such a small sample does not allow us to learn much about the chemistry of element 117. Ununseptium's position on the periodic table places it under the halogen gases such as fluorine and chlorine, but the strong capacity to capture electrons that makes these so reactive weakens as you go down the table, and in fact it is thought if one could ever produce enough to observe chemical interactions it would be more likely to lose electrons than gain them .
With a dozen new discoveries since he wrote The Elements, maybe it is time for Tom Lehrer to come out of retirement to add more lines to his song. Well we can hope.
Meanwhile Hinde has still greater dreams. "The big question is, how can we create elements 119 and 120?" To do this, however, a projectile heavier than 48Ca will need to be found. Hinde is working on identifying the best candidate.